Data access without internet access

[theBrain]

Hello, 

I am looking to create a very personal app to alert myself in the event of a particular heart condition during sleep.   From what I can tell about the Fitbit API, it is calling the "intraday" data via the fitbit cloud service so any and all data I would like to analyze can only come from the internet.  I would prefer to have direct data from the wearable going straight to the app for processing and then the data can be uploaded to the FB site if an internet connection is available.  But if no connection is available, then the devices are still able to perform their tasks.  

Is this possible with fitbit development or must all of my data come from fitbit servers?

Moderator edit: clarified subject and label

[AndrewFitbit]

@theBrain The data has to sync to Fitbit before it's available via the Web API. Also, the tracker can't communicate directly with your app, it will only communicate with the Fitbit app.